1. Field of the Invention
The present invention relates to a method of driving touch display and a touch display capable of increasing signal-to-noise ratio, and particularly to a method of driving touch display and a touch display that can utilize a channel division multiplexing driving method to increase a signal-to-noise ratio of a touch panel of the touch display.
2. Description of the Prior Art
Please refer to FIG. 1. FIG. 1 is a diagram illustrating three capacitive touch panels according to the prior art. As shown in FIG. 1, the prior art can divide capacitive touch panels into an out-cell capacitive touch panel, an on-cell capacitive touch panel, and an in-cell capacitive touch panel according to structures of the capacitive touch panels, wherein a touch panel and a liquid crystal panel of the out-cell capacitive touch panel adhere to each other; a process of touch sensing units of the on-cell capacitive touch panel is directly implemented on a color filter layer of the on-cell capacitive touch panel; and a process of touch sensing units of the in-cell capacitive touch panel is implemented in a liquid crystal layer of the in-cell capacitive touch panel. Currently, the out-cell capacitive touch panel is more popular. However, because thickness of touch panels of the on-cell capacitive touch panel and the in-cell capacitive touch panel is smaller, a touch panel designer gradually pays attention to the on-cell capacitive touch panel and the in-cell capacitive touch panel.
In in-cell capacitive touch panel technologies, a common type technology of integrating a common voltage layer and a touch sensing unit driving layer of a liquid crystal panel are the most popular. Although the common type technology has high integrity, structure and signal processing of a touch panel of the common type technology are more complicated. Please refer to FIG. 2. FIG. 2 is a diagram illustrating a common type touch panel 200 according to the prior art. As shown in FIG. 2, a common voltage layer 202 of a liquid crystal panel also simultaneously acts as a touch sensing unit driving layer, and a touch sensing unit driving layer 204 is installed on a color filter layer 206.
As shown in FIG. 2, because the common voltage layer 202 of the liquid crystal panel of the common type touch panel 200 simultaneously acts as the touch sensing unit driving layer, the prior art utilizes a time division multiplexing driving method to execute display and touch scanning of the common type touch panel 200. That is to say, the prior art utilizes the time division multiplexing driving method to execute display and touch scanning of the common type touch panel 200 within each horizontal synchronization signal blanking time of the common type touch panel 200, wherein the time division multiplexing driving method is also applied to the on-cell capacitive touch panel and the in-cell capacitive touch panel.
Because the prior art utilizes the time division multiplexing driving method to execute display and touch scanning of a block of a touch panel within each horizontal synchronization signal blanking time of the touch panel, scanning time is insufficient for the block of the touch panel. In addition, a frequency of a touch scanning signal of the touch panel is fixed and can not be adjusted, so a report rate of the touch panel is limited (e.g. 60 Hz). Further, because a number horizontal synchronization signal blanking time within a frame of the touch panel is finite, the prior art can not increase a signal-to-noise ratio of the touch panel even if the prior art utilizes an accumulated raw data method, resulting in performance of the touch panel being decreased.